EN ISO 5530-2:2025

SLOVENSKI STANDARD
01-marec-2025
Nadomešča:
SIST EN ISO 5530-2:2015
Pšenična moka - Fizikalne značilnosti testa - 2. del: Ugotavljanje reoloških
lastnosti z ekstenzografom (ISO 5530-2:2025)
Wheat flour - Physical characteristics of doughs - Part 2: Determination of rheological
properties using an extensograph (ISO 5530-2:2025)
Weizenmehl - Physikalische Eigenschaften von Teigen - Teil 2: Bestimmung der
rheologischen Eigenschaften mittels Extensograph (ISO 5530-2:2025)
Farines de blé tendre - Caractéristiques physiques des pâtes - Partie 2: Détermination
des caractéristiques rhéologiques au moyen de l'extensographe (ISO 5530-2:2025)
Ta slovenski standard je istoveten z: EN ISO 5530-2:2025
ICS:
67.060 Žita, stročnice in proizvodi iz Cereals, pulses and derived
njih products
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 5530-2
EUROPEAN STANDARD
NORME EUROPÉENNE
January 2025
EUROPÄISCHE NORM
ICS 67.060 Supersedes EN ISO 5530-2:2014
English Version
Wheat flour - Physical characteristics of doughs - Part 2:
Determination of rheological properties using an
extensograph (ISO 5530-2:2025)
Farines de blé tendre - Caractéristiques physiques des Weizenmehl - Physikalische Eigenschaften von Teigen -
pâtes - Partie 2: Détermination des caractéristiques Teil 2: Bestimmung der rheologischen Eigenschaften
rhéologiques au moyen de l'extensographe (ISO 5530- mittels Extensograph (ISO 5530-2:2025)
2:2025)
This European Standard was approved by CEN on 27 September 2021.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 5530-2:2025 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 5530-2:2025) has been prepared by Technical Committee ISO/TC 34 "Food
products" in collaboration with Technical Committee CEN/TC 338 “Cereal and cereal products” the
secretariat of which is held by AFNOR.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by July 2025, and conflicting national standards shall be
withdrawn at the latest by July 2025.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 5530-2:2014.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN website.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO 5530-2:2025 has been approved by CEN as EN ISO 5530-2:2025 without any
modification.
International
Standard
ISO 5530-2
Fourth edition
Wheat flour — Physical
2025-01
characteristics of doughs —
Part 2:
Determination of rheological
properties using an extensograph
Farines de blé tendre — Caractéristiques physiques des pâtes —
Partie 2: Détermination des caractéristiques rhéologiques au
moyen de l'extensographe
Reference number
ISO 5530-2:2025(en) © ISO 2025

ISO 5530-2:2025(en)
© ISO 2025
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: +41 22 749 01 11
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii
ISO 5530-2:2025(en)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Reagents . 3
6 Apparatus . 3
7 Sampling . 4
8 Procedure . 4
8.1 Determination of the moisture content of the flour .4
8.2 Preparation of apparatus .4
8.3 Test portion .5
8.4 Preparation of the dough .5
8.5 Determination .6
9 Expression of results . 6
9.1 General .6
9.2 Water absorption .6
9.3 Resistance to stretching .6
9.3.1 Maximum resistance .6
9.3.2 Resistance at constant deformation .7
9.4 Extensibility, E .7
9.5 Energy .8
9.6 Ratio (R/E) .8
10 Precision . 8
10.1 Interlaboratory tests .8
10.2 Repeatability .8
10.3 Reproducibility . .8
10.4 Comparison of two groups of measurements in two laboratories .9
11 Test report . 9
Annex A (informative) Description of the extensograph .10
Annex B (informative) Results of interlaboratory test .15
Annex C (informative) Fidelity data .52
Bibliography .54

iii
ISO 5530-2:2025(en)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out through
ISO technical committees. Each member body interested in a subject for which a technical committee
has been established has the right to be represented on that committee. International organizations,
governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely
with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are described
in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the different types
of ISO document should be noted. This document was drafted in accordance with the editorial rules of the
ISO/IEC Directives, Part 2 (see www.iso.org/directives).
ISO draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). ISO takes no position concerning the evidence, validity or applicability of any claimed patent
rights in respect thereof. As of the date of publication of this document, ISO had not received notice of (a)
patent(s) which may be required to implement this document. However, implementers are cautioned that
this may not represent the latest information, which may be obtained from the patent database available at
www.iso.org/patents. ISO shall not be held responsible for identifying any or all such patent rights.
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and expressions
related to conformity assessment, as well as information about ISO’s adherence to the World Trade
Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 34, Food products, Subcommittee SC 4, Cereals
and pulses, in collaboration with the European Committee for Standardization (CEN) Technical Committee
CEN/TC 338, Cereal and cereal products, in accordance with the Agreement on technical cooperation between
ISO and CEN (Vienna Agreement).
This fourth edition cancels and replaces the third edition (ISO 5530-2:2012), which has been technically
revised.
The main changes are as follows:
— a wheat flour interlaboratory test was performed in 2016 to evaluate the repeatability and reproducibility
of the test method specified in this document, and the results have been added as Annex B;
— more detailed procedure for electronic devices has been added.
A list of all parts in the ISO 5530 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.

iv
International Standard ISO 5530-2:2025(en)
Wheat flour — Physical characteristics of doughs —
Part 2:
Determination of rheological properties using an
extensograph
1 Scope
This document specifies a method using an extensograph for the determination of the rheological properties
of wheat flour doughs in an extension test. The recorded load–extension curve is used to assess the general
quality of flour and its response to improving agents.
The method is applicable to experimental and commercial flours from wheat (Triticum aestivum L.).
[5] [6]
NOTE 1 This document is related to ICC 114 and AACC Method 54-10 .
NOTE 2 For dough preparation, a farinograph is used (see 6.2)
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes
requirements of this document. For dated references, only the edition cited applies. For undated references,
the latest edition of the referenced document (including any amendments) applies.
ISO 712-1, Cereals and cereal products — Determination of moisture content — Part 1: Reference method
ISO 3696, Water for analytical laboratory use — Specification and test methods
ISO 5530-1, Wheat flour — Physical characteristics of doughs — Part 1: Determination of water absorption and
rheological properties using a farinograph
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
energy
capacity to do work
Note 1 to entry: For the purposes of this document, energy is determined as the area under a recorded curve. The
energy describes the work applied when stretching (3.6) a dough sample.
Note 2 to entry: When using a mechanical device, the area is measured by a planimeter and reported in square
centimetres. In electronic devices, this area is calculated automatically by the software.

ISO 5530-2:2025(en)
3.2
extensibility
E
distance travelled by the recorder paper from the moment that the hook touches the test piece until rupture
of (one of the strings of) the test piece
Note 1 to entry: In electronic devices, this is calculated automatically by the software.
Note 2 to entry: See 9.4 and Figure 1.
3.3
extensograph water absorption
volume of water required to produce a dough with a consistency of 500 farinograph unit (FU) after 5 min
mixing, under specified operating conditions
Note 1 to entry: Extensograph water absorption is expressed in millilitres per 100 g of flour at 14,0 % mass fraction
moisture content.
3.4
maximum resistance
R
m
mean of the maximum heights of the extensograph curves from two test pieces, provided that the difference
between them does not exceed 15 % of their mean value
Note 1 to entry: See 9.3.1 and Figure 1.
3.5
ratio
R/E
quotient of the maximum resistance, R , (3.4) and the extensibility (3.2) or the resistance after 50 mm
m
transposition of the recorder paper, R , and the extensibility
Note 1 to entry: In electronic devices, this is calculated automatically by the software.
Note 2 to entry: The ratio is an additional factor in the review of the dough behaviour.
3.6
resistance at constant deformation
R
mean of the heights of the extensograph curves after 50 mm transposition of the recorder paper from two
test pieces, provided that the difference between them does not exceed 15 % of their mean value
Note 1 to entry: In electronic devices, this is calculated automatically by the software.
Note 2 to entry: See 9.3.2 and Figure 1.
3.7
stretching
resistance of dough to extension and the extent to which it can be stretched until breaking, under specified
operating conditions
Note 1 to entry: The resistance is expressed in arbitrary units (extensograph unit, EU).
Note 2 to entry: The extent of stretching is expressed in millimetres.
4 Principle
Dough is prepared from flour, water and salt in a farinograph under specified conditions. A test piece is then
moulded on the balling unit and moulder of the extensograph into a standard shape. After a fixed period of
time, the test piece is stretched and the force required recorded. Immediately after these operations, the
same test piece is subjected to two further cycles of moulding, rest period and stretching.

ISO 5530-2:2025(en)
The size and shape of the curves obtained are a guide to the physical properties of the dough. These physical
properties influence the end-use quality of the flour.
5 Reagents
Use only reagents of recognized analytical grade, unless otherwise specified, and distilled or demineralized
water conforming to grade 3 in accordance with ISO 3696.
5.1 Sodium chloride of recognized analytical grade.
5.2 Optional release material.
Rice flour or starch (to avoid that the dough is sticking to the moulder and roller)
6 Apparatus
The usual laboratory apparatus and, in particular, the following shall be used.
1)
6.1 Extensograph, with a thermostat consisting of a constant temperature water bath (see Annex A),
with the following operating characteristics:
−1
— rotational frequency of the balling unit: (83 ± 3) min (r/min);
−1
— rotational frequency of the moulder: (15 ± 1) min (r/min);
— hook speed: (1,45 ± 0,05) cm/s;
— chart speed: (0,65 ± 0,01) cm/s; in electronic devices, this is recorded automatically by the device;
— force exerted per extensograph unit: (12,3 ± 0,3) mN/EU [(1,25 ± 0,03) gf/EU].
Some older instruments have a different calibration for force/unit deflection. The procedure specified can
be used with such instruments, but it is necessary for the different calibration to be taken into account when
comparing the results with instruments calibrated as above.
NOTE An electronic extensograph can be used, see Clause A.5.
2)
6.2 Farinograph, connected to a thermostat with the operating characteristics specified in ISO 5530-1.
6.3 Balance, capable of weighing to the nearest ±0,1 g.
6.4 Spatula, made of a non-metallic material.
6.5 Conical flask, of 250 ml capacity.
1) This document has been drawn up on the basis of the Brabender Extensograph, which is an example of a suitable
product available commercially. This information is given for the convenience of users of this document and does not
constitute an endorsement by ISO of this product. Equivalent products may be used if they can be shown to lead to the
same results.
2) This document has been drawn up on the basis of the Brabender Farinograph, which is an example of a suitable
product available commercially. This information is given for the convenience of users of this document and does not
constitute an endorsement by ISO of the product named. Equivalent products may be used if they can be shown to lead to
the same results.
ISO 5530-2:2025(en)
7 Sampling
Sampling is not part of the method specified in this document. A recommended sampling method is given in
[4]
ISO 24333 .
It is important that the laboratory receives a sample that is truly representative and that has not been
damaged or changed during transport and storage.
8 Procedure
8.1 Determination of the moisture content of the flour
Determine the moisture content of the flour using the method specified in ISO 712-1 or by near infrared
spectroscopy. The performances of the NIR should be demonstrated in accordance with ISO 12099 and reach
at least one standard error of prediction (SEP) ≤ 0,15 % determined over the entire scope of this document.
NOTE In comparison with ISO 712-1, the error of prediction for ISO 12099 is higher.
8.2 Preparation of apparatus
8.2.1 Turn on the thermostat (6.2) of the farinograph and circulate the water until the required
temperature is reached, prior to using the instrument. Before and during use, check the temperatures of:
— the thermostat;
— the mixing bowl of the farinograph, in the hole provided for this purpose;
— the extensograph cabinet.
All temperatures shall be (30 ± 0,2) °C.
8.2.2 For mechanical devices, adjust the arm of the pen of the extensograph so as to obtain a zero reading
when a cradle with both its clamps plus 150 g is placed in position. For electronic devices, the zero adjustment
is programmed to be done automatically at the start of the measurement.
8.2.3 Pour some water into the trough of each cradle support, so that the bottom is fully covered in order to
get a constant humidity, and place the supports, cradles and clamps in the cabinet at least 15 min before use.
8.2.4 For mechanical devices, uncouple the mixer of the farinograph from the driving shaft and adjust
the position of the counterweight(s) so as to obtain zero deflection of the pointer with the motor running
at the specified rotational frequency (see ISO 5530-1:2025, 6.1). Switch off the motor and then couple the
mixer. For electronic devices, the zero adjustment is programmed to be done automatically at the start of the
measurement.
For mechanical devices, lubricate the mixer with a drop of water between the back-plate and each of
the blades. Check that the deflection of the pointer is within the range (0 ± 5) FU with the mixing blades
operating at the specified rotational frequency in the empty, clean bowl. If the deflection exceeds 5 FU, clean
the mixer more thoroughly or eliminate other causes of friction. For electronic devices, the lubrication of the
blades is done with silicon fat.
For mechanical devices, adjust the arm of the pen so as to obtain identical readings from the pointer and the
recording pen.
For mechanical devices, adjust the damper so that, with the motor running, the time required for the pointer
to go from 1 000 FU to 100 FU is (1,0 ± 0,2) s.
8.2.5 The water added to the flour should have a temperature of (30 ± 0,5) °C.

ISO 5530-2:2025(en)
8.3 Test portion
If necessary, bring the flour to a temperature of between 25 °C to 30 °C
Weigh, to the nearest 0,1 g, the equivalent of 300 g of flour having a moisture content of 14 % mass fraction.
Let this mass, in grams, be m. See ISO 5530-1:2025, Table 1, for m as a function of moisture content.
Place the flour into the farinograph mixer. Cover the mixer and keep it covered until the end of mixing (see
8.4.2), except for the shortest possible time when water has to be added and the dough scraped down (see
ISO 5530-1:2025, A.1.2).
8.4 Preparation of the dough
8.4.1 Place (6,0 ± 0,1) g for the 300 g mixer or (1,0 ± 0,1) g for the 50 g mixer of the sodium chloride (5.1) in
the conical flask (6.5). Run in the amount of water that is necessary to prepare a dough of target consistency
and dissolve the salt.
8.4.2 Mix in the farinograph mixer at the specified rotational frequency (see ISO 5530-1:2025, 6.1) for
1 min or slightly longer. Pour the salt solution (see 8.4.1) within less than 25 s through a funnel into the
centre hole of the bottom part of the lid, when a whole-minute line on the recorder paper passes by the pen
or is automatically recorded by the electronic devices. When the dough forms, scrape down the sides of the
bowl with the spatula (6.4), adding any adhering particles to the dough without stopping the mixer. If the
consistency is too high, add a little more water to obtain a consistency of 500 FU after mixing for 5 min. Stop
mixing and clean the mixer.
In order to simplify the measurement and the reading, the recorder paper may be moved forward during
the pre-mixing of the flour. Do not move it backwards. For electronic devices, a time is registered; the
measurement can start at any time.
NOTE 1 With older models of the farinograph, where the bowl is covered by a single plate without a dosing hole in
the right corner (see ISO 5530-1:2025, A.1.2), the salt solution is poured into the right-hand front corner of the bowl.
NOTE 2 If the first dough meets the requirements of 8.4.3, test pieces from it can be moulded (see 8.4.4) and
stretched (see 8.5.1).
8.4.3 Make further mixings as necessary, until a dough is obtained:
— to which the salt solution and water have been added within 25 s;
— the consistency of which, measured at the centre of the curve after mixing for 5 min, is between 480 FU
and 520 FU.
8.4.4 Take a support with two cradles from the cabinet of the extensograph (6.1). Remove their clamps.
Remove the dough from the mixer. Weigh a (150 ± 0,5) g test piece rapidly. Place it rapidly in the balling unit
and perform 20 revolutions of the plate. Remove the dough from the balling unit and pass it once through the
moulder, ensuring that the test piece enters the back centrally, base first. Roll the test piece off the moulder
into the centre of a cradle and clamp it. Set the timer for 45 min. Weigh a second test piece. Ball, mould and
clamp it in the same way. Place the support with two cradles and test pieces in the cabinet.
Very sticky doughs (e.g. when dough remains on the moulder or the roller) may be dusted lightly with rice
flour or starch before being put into the moulder.
In the case of doughs showing substantial elastic recovery (which causes the upper part of the cradle to lift
up when placing the dough in it), the clamps should be held down for a few seconds to ensure that they fix
the dough properly.
Clean the farinograph mixer.
ISO 5530-2:2025(en)
8.5 Determination
8.5.1 Exactly 45 min after clamping the first test piece, place the first cradle in the balance arm of the
extensograph (6.1); the bridge between the two halves of the cradle shall be on the left-hand side so as not to
be touched by the stretching hook when travelling. Adjust the pen to zero force (not necessary for electronic
devices). Immediately start the stretching hook.
Observe the test piece (see 9.4, paragraph 2). After rupture of the piece, remove the cradle.
NOTE In recent models of the extensograph, the hook automatically returns to its upper position. With older
models, a switch can be used to stop the hook after breaking of the test piece and to initiate the return to its upper
position.
8.5.2 Collect the dough from the cradle and the hook. Repeat the balling and moulding operations as
specified in 8.4.4 on this test piece. Reset the timer for 45 min.
8.5.3 Turn the recorder paper back to the same starting position as for the first test piece force (not
necessary for electronic devices). Repeat the stretching operation (see 8.5.1) on the second test piece. Collect
the dough from the cradle and the hook. Repeat the balling and moulding operations (see 8.4.4) on the
second test piece.
8.5.4 Repeat the stretching, balling and moulding operations specified in 8.5.1 to 8.5.3, returning the
moulded test pieces to the cabinet. These operations take place after slightly more than 90 min from the end
of mixing.
8.5.5 Repeat the operation specified in 8.5.1, stretching both test pieces in turn. This operation takes place
after slightly more than 135 min from the end of mixing.
8.5.6 Other variations of this procedure, and evaluations of them, exist. However, they are not valid for use
with this document. In order to carry out quick and time-saving measurements, another procedure may be
suitable. The difference from the standard procedure is in the rest periods. Stretching after 45 min, 90 min
and 135 min after mixing are replaced by stretching after 30 min, 60 min and 90 min after mixing. The
shape and the size of the curves obtained differ from those of the standard extensograms. When the quick
procedure is used, it is necessary to state this in the test report.
9 Expression of results
9.1 General
To facilitate the calculations, a computer may be used. The extensograph has to be modified by adding an
electrical output for transferring the data to the computer. With the appropriate software, the computer
evaluates the diagram in accordance with 9.2 to 9.5 and documents the diagram and the results.
9.2 Water absorption
Calculate the extensograph water absorption, expressed in millilitres per 100 g of flour at 14 % mass fraction
moisture content for the 300 g mixer.
9.3 Resistance to stretching
9.3.1 Maximum resistance
Take as the maximum resistance, R , to stretching the mean of the maximum heights of the extensograph
m
curves (see Figure 1) from the two test pieces, provided that the difference between them does not exceed
15 % of their mean value.
ISO 5530-2:2025(en)
When using mechanical devices, the result should be read with an accuracy to the nearest 5 EU.
Report each of the mean values of R , R and R (mean values are calculated by electronic devices
m45 m90 m135
automatically).
Key
X time or extension (x/mm) E extensibility
Y force (EU) R maximum resistance
m
R resistance after 50 mm transposition of the recorder paper
Figure 1 — Representative extensogram showing the commonly measured indices
9.3.2 Resistance at constant deformation
Some people prefer to measure the height of the curve at a fixed extension of the test piece, usually
corresponding to 50 mm transposition of the recorder paper or electronic chart. The extension is measured
from the moment that the hook touches the test piece, i.e. when the force is suddenly different from zero.
This parameter was not evaluated in the ring tests.
Take as the result of the resistance to stretching at constant deformation, R , the mean of the heights of the
extensograph curves after 50 mm transposition of the recorder paper or electronic chart (see Figure 1) from
the two test pieces, provided that the difference between them does not exceed 15 % of their mean value.
When using mechanical devices, the result should be read with an accuracy to the nearest 5 EU.
Report each of the mean values of R , R and R (mean values are calculated by electronic devices
50,45 50,90 50,135
automatically).
Owing to the greater depression of the cradle, a more resistant test piece is extended to a lesser extent at
50 mm transposition of the recorder paper or electronic chart than a less resistant test piece. It is possible,
by means of a suitable template, to read the resistances of all test pieces at the same net extension. If such a
template is used, it is necessary to mention this in the test report.
9.4 Extensibility, E
Measure the extensibility until rupture. Rupture is indicated on the extensograph curve either by a smooth
fall of the curve almost to zero force, or by a sharp break in the curve (see Figure 1).
Beyond the breaking point, the course of the recording depends on the inertia of the lever system and on the
time interval between the breaking of the two strings of the test piece. For measurement of the extensibility,
the curve is supposed to proceed, from the breaking point, along a circular ordinate line (dashed line in
Figure 1) down to zero force. To identify the breaking point on the curve properly, it is necessary to observe
the test piece when breaking.
Take as the result of the extensibility the mean distance on the extensograph curves from the two test
pieces, provided that the difference between them does not exceed 9 % of their mean value.
Report each of the mean values of E , E and E to the nearest millimetre.
45 90 135
ISO 5530-2:2025(en)
9.5 Energy
Determine the energy by measuring the area under the recorded curve using a planimeter (the area is
calculated by electronic devices automatically). Report in square centimetres.
9.6 Ratio (R/E)
Determine the ratio R/E.
10 Precision
10.1 Interlaboratory tests
Interlaboratory tests were performed in 2016 by Cereal & Food Expertise (see Annex B).
NOTE The repeatability and reproducibility values derived from these interlaboratory tests are not necessarily
applicable to other measurement ranges and matrices than those given.
10.2 Repeatability
The absolute difference between two independent single test results, obtained using the same method on
identical test material in the same laboratory by the same operator using the same equipment within a short
interval of time, will in not more than 5 % of cases be greater than the values given in Table 1.
Table 1 — Repeatability data obtained by using extensograph
Characteristic 45 min 90 min 135 min
Energy (cm ) r = 0,155 4 X – r = 0,160 72 X –
r = 13,3
1,909 88 0,322 28
Extensibility (E, mm) r = 13,8 r = 14,2 r = 13,9
Maximum resistance (R , EU) r = 44,8 r = 61,8 r = 64,8
m
Resistance at constant deformation (R , EU) r = 33,9 r = 45,8 r = 47,4
Ratio (R /E) r = 0,37 r = 0,49 r = 0,51
m
Ratio (R /E) r = –1,067 08
r = 0,52 r = 0,44
X + 2,105 88
NOTE X is the arithmetic mean of the two determinations.
10.3 Reproducibility
The absolute difference between two single test results, obtained using the same method on identical test
material in different laboratories with different operators using different equipment, will in not more than
5 % of cases be greater than the values given in Table 2.

ISO 5530-2:2025(en)
Table 2 — Reproducibility data obtained by using extensograph
Characteristic 45 min 90 min 135 min
Energy (cm ) R = 0,160 72 X – R = 0,356 16 X –
R = 21,7
3,495 52 7,641 2
Extensibility (E, mm) R = 21,1 R = 22,3 R = 23,4
Maximum resistance (R , EU) R = 65,3 R = 95,1 R = 104,5
m
Resistance at constant deformation (R , EU) R = 51 R = 76,6 R = 78,1
Ratio (R /E) R = 0,55 R = 0,75 R = 0,78
m
Ratio (R /E) R = –1,147 72
R = 0,66 R = 0,69
X + 2,399 32
NOTE X is the arithmetic mean of the two determinations.
10.4 Comparison of two groups of measurements in two laboratories
The critical difference (CD ) between two averaged values each obtained in two different laboratories from
R
two test results under repeatability conditions is equal to Formula (1):
1 1
22 22
Cs=−28,(s 1−− ),=−28 ss05, (1)
D Rr Rr
2nn2
where
s is the standard deviation of repeatability;
r
s is the standard deviation of reproducibility;
R
n and n are the number of test results corresponding to each averaged value.
1 2
See the calculated values for the different levels of each parameter.
Data are shown in Annex C.
11 Test report
The test report shall contain at least the following information:
a) all information necessary for the complete identification of the sample;
b) the sampling method used, if known;
c) the test method used, with reference to this document, i.e. ISO 5530-2;
d) all operating details not specified in this document, or regarded as optional, together with details of any
incidents that could have influenced the test result(s);
e) the test result(s) obtained;
f) if the repeatability has been checked, the final calculated result obtained;
g) the date of the test.
ISO 5530-2:2025(en)
Annex A
(informative)
Description of the extensograph
A.1 General description
The extensograph comprises two units:
a) the extensograph unit itself (see Clause A.2);
b) a thermostat for the circulating water (see Clause A.3).
The extensograph is used in conjunction with the farinograph, which also comprises a thermostat (see
ISO 5530-1).
A.2 Extensograph unit
A.2.1 General
The extensograph unit is mounted on a heavy cast-iron base plate having four levelling screws and consists of:
a) a balling unit or rounder (see A.2.2);
b) a moulder or shaper (see A.2.3);
c) cradles and clamps for holding the test pieces, and cradle supports;
d) a three-section rest cabinet (see A.2.4);
e) a device for stretching a test piece (see A.2.5);
f) means for recording the resistance to stretching and the extensibility of the test piece in the form of
extensograms (see A.2.6).
The stretching device and means for recording are illustrated diagrammatically in Figure A.1.

ISO 5530-2:2025(en)
Key
1 test piece 6 lever system
2 cradle 7 scale
3 clamp for cradle 8 recorder
4 electric motor 9 dash-pot damper
5 stretching hook
Figure A.1 — Diagram of the stretching device and recorder of the mechanical extensograph
A.2.2 Balling unit
The balling unit consists of a bottomless box with a loaded lid. Beneath the box a flat plate rotates. In its
centre, it carries a pin on which the dough is impaled. The rotational frequency of the balling unit shall be
−1
(83 ± 3) min .
Water from the thermostat circulates through the hollow side walls of the box to control its temperature.
−1
Some instruments made before 1965 can have a rotational frequency of 112 min . If such an instrument is
used, mention this in the test report.
A.2.3 Moulder
The moulder consists of a horizontal roller revolving inside an incomplete cylinder at a rotational frequency
−1
of (15 ± 1) min . The cylinder has a metal plate attached to its inner wall. The dough is thus subjected to a
moulding action between the roller and the metal plate.

ISO 5530-2:2025(en)
Water from the thermostat circulates through the hollow incomplete cylinder to control its temperature.
A.2.4 Rest cabinet
The temperature-controlled rest cabinet consists of three sections, each one for one cradle support with two
cradles, and each one with a door.
The test pieces, having been balled and moulded, are rested in the cradles on their supports in the rest
cabinet. Each of the cradle supports carries two cradles and has a trough containing water to prevent
skinning of the test pieces.
A.2.5 Stretching device
The cylindrical test piece, in a cradle, is supported in a horizontal position by two arms attached to one
end of a pivotally mounted lever, which carries a counterweight at the other end. A hook in contact with the
centre of the upper side of the test piece is moved vertically downwards by the action of an electric motor, at
a speed of (1,45 ± 0,05) cm/s, thereby stretching the test piece. Downward movement of the dough hook is
continued until the test piece breaks.
The mechanism actuating the stretching hook has automatic limit switches, which terminate the movement
when the hook reaches either the top or the bottom limit. In recent models of extensograph, the hook, having
reached the bottom position, automatically returns to its top position.
The resistance of the dough to stretching results in a downward movement of the lever carrying the cradle
with the test piece.
A.2.6 Recorder
Movement of the lever carrying the cradle with the test piece is transmitted by a further system of levers to
a pen, which is thereby moved over a band of paper, recording the movement in the form of an extensogram.
Movements of the lever system and recorder pen are damped by a piston immersed in oil. The piston is
connected to the lever carrying the cradle.
The paper for th
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